The primary benefit of free tagging is that we know the classification makes sense to users. It can also reveal terms that “experts” might have overlooked.

For instance, check out the nearly 250 photos on Flickr tagged as Squared Circle. Who could have guessed this would be a category? (You can keep up-to-date on this group of photos using the handy Squared Circle tag’s RSS feed.)

(And heck if my research isn’t leading back to George Lakoff. Strange how that happens.)